Omega Vehicle Security OM5-C manual P1 and P2 Connector, Adjacent Channel Jumpers, Power, Fusing

ELECTRICAL

P1 AND P2 CONNECTOR

Connection to the host system is made at connectors P1 and P2. These connectors are electrically equivalent. Two connectors are provided to allow both analog input and analog output from host systems having individual input and output connectors.

ADJACENT CHANNEL JUMPERS

Adjacent channels may be connected together to provide an isolated output signal from an isolated input module, providing two levels of 1500V isolation. This capability is provided with the 15 jumpers labeled JP1 through JP15 on headers E1, E2, and E3. A simplified drawing of the OM5- BP-16-C schematic for Channel 1 through 4 is shown in Figure 3.

Example: Assume an OM5-IMV input module is installed in Channel 1 position and an OM5-IVI output module is installed in Channel 2 position. If JP1 is installed, the output of Channel 1 is connected to the input of Channel 2, which provides two levels of 1500V isolation.

				HD10, E1
P2	P1	JP1		JP2		JP3	JP4
		1	2	3	4	5	6
	1
	5
	7
	11
	13
	20	VOUT	20	VOUT	20	VOUT	20
	VOUT
	18	VIN	18	VIN	18	VIN	18
	VIN
	CH 1	CH 2		CH 3		CH 4
FIGURE 3. OM5-BP-16-C Adjacent Channel Jumpers.

POWER

The OM5-BP-16-C backpanel requires external +5VDC ±5% power. The chassis mounted OMX-976-C power supplies have adequate capacity to power any combination of modules.

FUSING

The OM5-BP-16-C backpanel power is fuse protected through F1. This is a Littlefuse type 252004, 4 amp fuse. Zener diode DZ1 provides extra protection by clamping the input power voltage to +5.6V. If the input supply voltage connection is reversed, this zener diode will be forward biased and fuse F1 will be blown.

GROUNDING

Figure 4 details the optional ground jumper configuration available on the OM5-BP-16-C backpanel. Jumpers J1, J3, and J4 are factory installed.

Jumper J1 connects the AGND shield wires (pins 3, 6, 9, 12, 15, 18, 21, and

24)to the backpanel signal ground. This provides a ground connection between the host system and backpanel. Jumper J1 is required if output modules are used, or if there is no high impedance sense input (input low of a differential or pseudo-differential system) on the host measurement sys- tem.

Jumper J3 connects the SENSE line (pin 25) to the backpanel signal ground. If the host system has the capability, this allows measuring the OM5-BP-16- C ground potential.

For proper operation of the output switch or track-and-hold circuit when using the OM5 backpanels, a current path must exist between the host control logic power common and module I/O Common (module pin 19). This path can be established on the OM5-BP-16-C via jumper J4. If this connection exists elsewhere in the system, jumper J4 should be removed since possible ground loops could exist. Other connections of power ground and signal

P2	P1
	3			OM5 Module
	6
	9
	12
	15	AGND
	18			I/O COM 19	16	PWR COM
	21
	24		J3	J4
	25	Sense
		J2	J1	Power Common
			R1	Signal Ground
				and
				Grounding Bolt
FIGURE 4. OM5-BP-16-C Grounding Diagram.

ground usually occur at the A/D or D/A converter of the host measurement system.

If the connection of power common and AGND shield wires exists in the host measurement system, an optional resistive connection between AGND and the backpanel signal ground can be made via R1. R1 can be as large as 10K ohms; 100 ohms is a recommended value. Jumper J2 can be used to connect the SENSE line to R1 when this ground configuration is used.

For full protection against large electrical disturbances on the field-side of the OM5 modules, a #10-32 ground stud is provided on the backpanel. An electrical connection between this ground stud and system ground should be provided with a large gauge wire of the shortest possible length. When this connection is made, a possible ground loop could result through the AGND shield wires and backpanel signal ground. If the application involves only input modules and a differential input is used by the host measurement system, J1 should be removed. Remember that J1 is required if output modules are used or if the host system does not have differential inputs.

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